In various aspects of sub surface activities such as hydrocarbon exploration and production, Carbon Dioxide sequestration, etc. one or more fiber optic cables having one or more optical sensors formed therein or connected thereto may be employed to obtain information from downhole locations. For example, by embedding or attaching a fiber optic cable to a structure, one can monitor the dynamic shape or relative position of the structure independently from temperature or load effects. As the fiber optic cable bends and/or stretches, the optical path of radiation propagating through the fiber is changed. Information pertaining to the shape of the structure is manifest in the phase of radiation propagating within the fiber and is therefore extractable using interferometric techniques. Several factors, however, can affect the reliability of such measurements. For example, the shape of the structure is calculated by comparing the measured waveform and an earlier, “zero-strain” waveform, and may not account for localized effects such as twisting. Because the reliability of shape information regarding inaccessible structures, such as a borehole, is crucial to maintenance and operation, the industry is receptive to advancements in measurement systems and methods.